Mesangial cell
From Free net encyclopedia
Mesangial cells are specialized cells around blood vessels in the kidneys.
Anatomical Location
Mesangial cells are located among the glomerular capillaries within a renal corpuscle. They are also found outside the glomerulus near the macula densa. In this location they are called lacis cells.
Function
Glomerular capillaries consist of endothelial cells with large fenestrations, and are therefore very permeable ("leaky") for most solutes in blood plasma.
Mesangial cells are specialized pericytes that are thought to aid in the regulation of glomerular filtration. They provide structural support for and regulate blood flow of the glomerular capillaries by their contractile activity. They are also major contributors to the extracellular matrix which contains fibronectin, type IV collagen, perlecan, and laminin. Mesangial cells secrete prostaglandins and endothelins and respond to angiotensin II. Mesangial cells also phagocytose glomerular basal lamina components and immunoglobulins.
Mesangial cells, in combination with the Macula Densa of the Distal Convoluted Tubule and Juxtaglomerular cells of the Afferent Arteriole, form the Juxtaglomerular Apparatus. This apparatus controls blood pressure through the Renin-Angiotensin-Aldosterone system.
References
Tortora GJ., & Grabowski SR., Principles of Anatomy and Physiology 10th Ed. John Wiley & Sons
Shannon Armstrong